Doctors in America are advising worried patients to buy painters’ masks as a precaution against the global outbreak of swine flu that appears to have spread from Mexico to the United States, New Zealand and possibly Europe.

With the worldwide death toll standing at about 81 and with about 1,300 people infected, authorities across the globe are torn between the desire to slow down a potential flu pandemic and the need to avoid bringing major cities on every continent to an economic standstill.

As of today, the US was still allowing people to cross the border from Mexico – where it is thought the swine flu emerged last week – although customs officials at the San Ysidro and Otay Mesa border crossings were given protective masks. It is thought that eight people in US border towns have gone down with swine flu, along with others in Kansas and New York.

There have been no deaths north of the Mexican border, however, and as of today the anti-viral drugs Tamiflu and Relenza were readily available from pharmacies in major cities. Several of those affected in the US have made full recoveries.

Earlier today the European Commission said that there were no known cases in Europe, but within hours three suspected cases were being investigated in Spain, which has a large Mexican émigré population, in the cities of Bilbao, Valencia and Albacete. All three sufferers returned recently from Mexico. Spanish authorities are contacting passengers who were on the same flights.

Two suspected cases have been also been reported in southern France.

A suspected British case, a member of a British Airways cabin crew who started to experience flu-like symptoms on a flight from Mexico to Heathrow, was given the all-clear this morning.

However, ten teenagers from New Zealand who returned home from Mexico yesterday are thought to be suffering from the disease. None is seriously ill, the country's Health Minister said.

One of the greatest concerns over the new strain of flu is that it is seems to target young, healthy adults – the same group affected by the Spanish flu pandemic of 1918, which killed up to 100 million people.

Medical experts will meet on Tuesday to advise the World Health Organisation (WHO) on whether to raise the current pandemic alert level.

“We need more epidemiological evidence from Mexico before the experts would be in a position to advise on a pandemic change,” Gregory Hartl, a WHO spokesman, said.